fix unit test failure on Windows

[andyzhangx]

What happened:
If some tests could not run on Windows, just skip it, refer to kubernetes-csi/csi-driver-smb#101

>go test -v -race ./pkg/azurefile/...
=== RUN   TestGetCloudProvider
W0906 15:34:40.110551   29660 azure.go:42] get kubeconfig() failed with error: unable to load in-cluster configuration, KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT must be defined
E0906 15:34:40.111552   29660 azure.go:71] Failed to load config from file: C:\k\azure.json
W0906 15:34:40.111552   29660 azure.go:42] get kubeconfig(/tmp/non-exist.json) failed with error: CreateFile /tmp/non-exist.json: The system cannot find the file specified.
E0906 15:34:40.111552   29660 azure.go:71] Failed to load config from file: C:\k\azure.json
W0906 15:34:40.112550   29660 azure.go:42] get kubeconfig(empty-kube-config) failed with error: invalid configuration: no configuration has been provided, try setting KUBERNETES_MASTER environment variable
W0906 15:34:40.133552   29660 azure_config.go:52] Failed to get cloud-config from secret: failed to get secret azure-cloud-provider: Get https://localhost:8080/api/v1/namespaces/kube-system/secrets/azure-cloud-provider: getting credentials: exec: exec: "foo-command": executable file not found in %PATH%, skip initializing from secret
E0906 15:34:40.133552   29660 azure.go:71] Failed to load config from file: C:\k\azure.json
W0906 15:34:40.133552   29660 azure.go:42] get kubeconfig() failed with error: unable to load in-cluster configuration, KUBERNETES_SERVICE_HOST and KUBERNETES_SERVICE_PORT must be defined
--- FAIL: TestGetCloudProvider (0.03s)
    azure_test.go:137: desc: [failure] out of cluster, no kubeconfig, no credential file,
         input: "", GetCloudProvider err: Failed to load config from file: C:\k\azure.json, cloud not get azure cloud provider, expectedErr: Failed to load config from file: /etc/kubernetes/azure.json, cloud not get azure cloud provider
    azure_test.go:137: desc: [failure] out of cluster & in cluster, specify a non-exist kubeconfig, no credential file,
         input: "/tmp/non-exist.json", GetCloudProvider err: Failed to load config from file: C:\k\azure.json, cloud not get azure cloud provider, expectedErr: Failed to load config from file: /etc/kubernetes/azure.json, cloud not get azure cloud provider
    azure_test.go:137: desc: [failure] out of cluster & in cluster, specify a fake kubeconfig, no credential file,
         input: "fake-kube-config", GetCloudProvider err: Failed to load config from file: C:\k\azure.json, cloud not get azure cloud provider, expectedErr: Failed to load config from file: /etc/kubernetes/azure.json, cloud not get azure cloud provider
=== RUN   TestNewFakeDriver
--- PASS: TestNewFakeDriver (0.00s)
=== RUN   TestAppendDefaultMountOptions
--- PASS: TestAppendDefaultMountOptions (0.00s)
=== RUN   TestGetFileShareInfo
--- PASS: TestGetFileShareInfo (0.00s)
=== RUN   TestGetStorageAccount
--- PASS: TestGetStorageAccount (0.00s)
=== RUN   TestGetValidFileShareName
W0906 15:34:40.140550   29660 azurefile.go:324] the requested volume name ("aq") is invalid, so it is regenerated as ("pvc-file-dynamic-6c5e4d43-f013-11ea-aa6a-00155de1a4f6")
--- PASS: TestGetValidFileShareName (0.00s)
=== RUN   TestCheckShareNameBeginAndEnd
--- PASS: TestCheckShareNameBeginAndEnd (0.00s)
=== RUN   TestGetSnapshot
--- PASS: TestGetSnapshot (0.00s)
=== RUN   TestIsCorruptedDir
--- FAIL: TestIsCorruptedDir (0.00s)
    azurefile_test.go:406: failed to create curruptedPath: symlink C:\Users\xiazhang\AppData\Local\Temp\csi-mount-test525504375 C:\Users\xiazhang\AppData\Local\Temp\csi-mount-test525504375\curruptedPath: A required privilege is not held by the client.
=== RUN   TestNewDriver
--- PASS: TestNewDriver (0.00s)
=== RUN   TestGetFileURL
--- PASS: TestGetFileURL (0.00s)
=== RUN   TestGetAccountInfo
--- PASS: TestGetAccountInfo (0.00s)
=== RUN   TestCreateDisk
--- FAIL: TestCreateDisk (0.00s)
panic: open /dev/urandom: The system cannot find the path specified. [recovered]
        panic: open /dev/urandom: The system cannot find the path specified.

goroutine 85 [running]:
testing.tRunner.func1(0xc000395500)
        c:/go/src/testing/testing.go:874 +0x6a6
panic(0x2352da0, 0xc00046b830)
        c:/go/src/runtime/panic.go:679 +0x1c0
github.com/rubiojr/go-vhd/vhd.check(...)
        C:/Users/xiazhang/go/pkg/mod/github.com/rubiojr/go-vhd@v0.0.0-20200706105327-02e210299021/vhd/util.go:31
github.com/rubiojr/go-vhd/vhd.uuidgenBytes(0xc0001d97e0, 0x8, 0xc000024a40)
        C:/Users/xiazhang/go/pkg/mod/github.com/rubiojr/go-vhd@v0.0.0-20200706105327-02e210299021/vhd/util.go:23 +0x135
github.com/rubiojr/go-vhd/vhd.CreateFixedHeader(0x14, 0xc0001d97e0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, ...)
        C:/Users/xiazhang/go/pkg/mod/github.com/rubiojr/go-vhd@v0.0.0-20200706105327-02e210299021/vhd/vhd.go:188 +0x8b6
sigs.k8s.io/azurefile-csi-driver/pkg/azurefile.createDisk(0x2892fa0, 0xc00008e0c8, 0x256a82e, 0x17, 0x2550b2c, 0x3, 0x25539c8, 0x6, 0x25a155f, 0x35, ...)
        C:/Users/xiazhang/go/src/sigs.k8s.io/azurefile-csi-driver/pkg/azurefile/azurefile.go:381 +0x93
sigs.k8s.io/azurefile-csi-driver/pkg/azurefile.TestCreateDisk(0xc000395500)
        C:/Users/xiazhang/go/src/sigs.k8s.io/azurefile-csi-driver/pkg/azurefile/azurefile_test.go:622 +0x4a7
testing.tRunner(0xc000395500, 0x26135e0)
        c:/go/src/testing/testing.go:909 +0x1a1
created by testing.(*T).Run
        c:/go/src/testing/testing.go:960 +0x659
FAIL    sigs.k8s.io/azurefile-csi-driver/pkg/azurefile  2.388s
FAIL

What you expected to happen:

How to reproduce it:

Anything else we need to know?:

Environment:

• CSI Driver version:
• Kubernetes version (use kubectl version):
• OS (e.g. from /etc/os-release):
• Kernel (e.g. uname -a):
• Install tools:
• Others:

could you work on this? @mayankshah1607 thanks.

[mayankshah1607]

@andyzhangx yeah, sure thing! :)